In testing situations of medical or dental students for example it is difficult for an instructor to let the student know the correct answer to a question immediately after he has made a response thereto and before going on to the next question. If the responses are made on a sheet of paper the students have the possibility of correcting wrong responses or delaying responses until the correct answer is known. Accordingly, it is common practice to withhold the answers until the student sheets are turned in. However, the ability of immediate feedback of correct answers during the test is indispensable in some cases, namely, when the student's decision-making ability should be evaluated and when one decision influences the next decision. Accordingly, any system which intends to test the ability for this type of decision-making in sequence must fulfill two objectives: (1) it must reveal only as much information at a time as is needed to make the next decision; and (2) the students' decisions must be recorded immediately and unalterably.
There are at present two systems in use which fulfill the foregoing objective. One of these is the computerized classroom wherein each student's desk is equipped with multiple choice pushbuttons which are wired to a computer. A video tape of the patient could be presented and stopped whenever the student has to make a decision concerning diagnosis and treatment planning. When all students have punched their responses into the computer, the video tape is restarted for the next section until the next decision is to be made. A disadvantage of this system is the high cost of equipment and installation thereof and furthermore it can only be used in the particular classroom which is equipped with such special desks. The other system is the written simulation system in which the testing technique employs invisible print which appears when the student applies a special marking pen. This type of test does conceal parts of the information until certain decisions have been made by the student and scoring is accomplished by counting the number of right and wrong choices of responses which have been made visible by the student. The disadvantage of this written simulation system is the fact that the student makes his decision on the basis of a written description of the patient rather than direct observation of an act or audio visual material such as movie film or video tape.